High Quality Materials: Made of high quality neoprene and lycra, it is easy to fold, sweat resistance, no smell, the armband is flexible, rollable. No pressure, comfortable to wear Touch ID technology: Armband; fully has touch sensitivity. With high sensitivity and high definition, you can easily access any function of your phone without having to take your phone out. (Please make sure fingerprint function is not available.) Humanized Design: The armband has a key slot and earphone hole, so don't worry about putting the key in your pocket or losing it in the gym and running around. You can place your phone safely and allow you to listen to music freely. Night Sports Safety: Reflective tape surrounds the screen window and armband to ensure visibility and safety for night running. Wide Compatibility:; running armband is suitable for mobile phones under 6.1 inch, such as 13/13 Pro/12/12 Pro/11/11 Pro/XR/X/8/7/6 Plus. The armband has two built-in slots to adjust the length, suitable for most people. Size A: 8.3-11.8 inches [21-30 cm], size B: 11.8-15.7 inches [30-40cm]. It also comes with an extension strap.